Device for building up high-pressure impulse jets of liquid

ABSTRACT

The present invention provides a device for building up highpressure impulse jets of liquid upon an impact delivered by a piston accelerated by compressed gas upon liquid disposed in a chamber provided with an aperture for the liquid outflow by jets; to bring the piston back to its initial position after an impact, the space of the cylinder before the piston being communicated with a liquid-supplying pressure main, and, to drain the liquid during the piston acceleration, the sidewalls of the cylinder are provided with drain apertures overlapped by a movable member of a locking mechanism.

v United States Patent Inventor v Faina Fedorovna Voitsekhovskaya ulitsaAkademicheskaya, Kottedzk 2, Novosibirsk, U.S.S.R. Appl. No. 873,860Filed Nov. 4, 1969 Patented Dec. 7, 1971 DEVICE FOR BUILDING UPHIGH-PRESSURE [56] References Cited UNITED STATES PATENTS 3,412,554 1[/1968 Voitsekhovsky et al 360/545 HA Primary Examiner-Martin P.Schwadron Assistant Examiner-A. M. Zupcic Attorney-Waters, Roditi,Schwartz & Nissen ABSTRACT: The present invention provides a device forbuilding up high-pressure impulse jets of liquid upon an impactdelivered by a piston accelerated by compressed gas upon liquid disposedin a chamber provided with an aperture for the liquid outflow by jets;to bring the piston back to its initial position after an impact, thespace of the cylinder before the piston being communicated with aliquid-supplying pressure main, and, to drain the liquid during thepiston acceleration, the sidewalls of the cylinder are provided withdrain apertures overlapped by a movable member of a locking mechanism.

IMPULSE JETS 0F LIQUID 4 Claims, 3 Drawing Figs. I

U.S. Cl ..60/54.5 I-IA, 60/54.5 HA, 60/l0.5, 60/51, 60/57 Int. Cl FlSb7/00 Field of Search 60/545, 54.6 HA

PATENTEU DEC 7 ISYI SHEET 2 [IF 3 PATENTED DEC 7 ml SHEET 3 [)F 3 DEVICEFOR BUILDING UP HIGH-PRESSURE IMPULSE JETS OF LXQUID The presentinvention relates to devices for building up high-pressure impulse jetsof liquid, created as a result of impacts delivered by a piston uponliquid in a chamber having an aperture for the outlet of pressurizedliquid, and, more particularly, to devices in which the return of thepiston to its initial position after an impact is effected by theliquid.

The device according to the present invention may be used for crushingrocks by direct action of a high pressure jet; for hydraulic stamping,when the pressurized liquid flowing out of the chamber is delivered intoa closed die having a blank disposed therein; as well as for forging,pressing and cutting metals, when pressurized liquid acts upon themovable piston carrying a working tool.

Known in the prior art are devices for building up high-pressure impulsejets of liquid (for example, British Pat. No. 1,081,076; US. Pa. No.3,412,554; French Pat. No. 1,415,034 to Voitzechovsky B. V. et al.'),which comprise a cylinder having a piston disposed therein and dividingits space into two chambers. The first chamber communicates with acompressed gas tank, whereas the other one is filled up with liquid andhas an aperture for pressurized liquid forced out as a result of animpact delivered .thereupon by a piston accelerated by compressed gas inthe first chamber.

According to the principle of the piston retraction into its initialposition after an impact, done in order to compress the gas in the firstchamber, the known devices are divided into two types.

The devices of one type have anactuating mechanism used for retractingthe strike piston and comprising at least one power cylinder whosemovable part interacts periodically with the strike piston of the devicewith the aid of a cam-gripping arrangement.

1n the devices of the other type the strike piston is retracted to itsinitial position after an impact by supplying pressurized liquid intothe cylinder space from the side of the second chamber, said liquidbeing drained through apertures in the sidewall of the cylinder duringthe piston working stroke in the direction of the second chamber. Duringthe piston return movement said apertures are overlapped by a movablemember of the locking mechanism and are opened by the same member fordraining liquid from the cylinder space in front of the piston at theend of the reverse 'stroke of the latter after an impact.

The operation of the locking mechanism is controlled by a slide valveinserted into a liquid-supplying pressure main, the body of the slidevalve being secured in the face wall of the cylinder at the side ofthe'first chamber, and the movable member thereof projecting into saidchamber and interacting with the piston during its coming to the initialposition after an impact.

In order to communicate the cylinder space in front of the piston withthe drain by the moment the piston is accelerated by the compressed gas,use was made of a means providing for the slowed-down motion of thepiston at the beginning of its working stroke in the direction of thesecond chamber. This means was formed by a duct made in the piston and avalve mounted in said duct and providing for gradual flow of thecompressed gas from the tank into the first chamber of the cylinderuntil the piston opened the ports communicating the compressed gas tankwith the first chamber, whereupon its acceleration was started. Duringthe slowed-down motion of the piston the movable member openedcompletely the drain apertures so that the piston could be freelyaccelerated and deliver an impact upon the liquid contained in thesecond chamber.

The slowed-down motion decreased the number of impacts the pistondelivered per unit time and, consequently, the efficiency of the device.

The principal object of the invention is to increase the efficiency ofthe device, i.e., to increase the number of impacts delivered by thepiston per unit time by way of improving the locking mechanism.

It is another object of the invention to simplify the design of thedevice and to make it more reliable in operation.

According to the invention the proposed improvement consists in that thedevice of the invention is provided with a means adapted for the initialopening of drain apertures by a movable member to the moment the pistonmoves towards the second chamber, and with a means providing for thefull opening of the drain apertures by the movable member under theeffect of the flow of liquid forcedout of the cylinder space during thepiston travel towards the second chamber.

The proposed technical solution provides for automatic opening of thedrain apertures synchronously with the piston travel owing to therepulsion of the movable member by the liquid forced by the piston outof the cylinder space during the working stroke.

It is preferable that the means providing for the full opening of thedrain apertures by the movable member be essentially a flange providedon said member and arranged with a gap in a cylindrical recess in thelocking mechanism body, and a main space provided in said body, saidspace being opened at the side of the flange and periodicallydiscommunicated from the drain apertures of the cylinder by the movablemember.

in one embodiment of the invention the means adapted for in the initialopening of the drain apertures by the movable member is formed by anauxiliary space in the body of the locking mechanism, communicated withthe pressure main and adapted to receive the butt end portion of themovable member, said auxiliary space being in constant communicationwith the main space in the body of the locking mechanism. 4

in another embodiment of the invention the last described means isformed by a cross member connected by rods to the movable member,abutting the rear portion of the cylinder and having a projectionentering the first chamber of the cylinder and cooperating with thepiston at the end of its reverse stroke after an impact.

The following description of possible embodiments of the presentinvention is given with reference to the accompanying drawings, inwhich:

FIG. 1 shows a longitudinal section of the proposed device, in which thebody of the locking mechanism has a main and an auxiliary spaces;

FIG. 2 shows a longitudinal section of the proposed device, in which themovable member of the locking mechanism is connected by rods with amovable cross member;

FIG. 3 is an enlarged partial view of the longitudinal'section of thelocking mechanism of the device, as shown in H6. 1.

As shown in FIGS. 1 and 2, the proposed device comprises a cylinder 1housing a piston 2 dividing the space of the latter into the twochambers 3 and 4. The first, low-pressure, chamber 3 is communicatedthrough ports 5 with tanks 6 containing compressed gas, said tanks 6being secured to the cylinder 1. The other, high-pressure, chamber 4filled up with liquid has an aperture 8 provided in the face wall 7 ofthe cylinder 1 and designed for the outlet of pressurized liquid afteran impact has been delivered thereupon by the piston 2 advancing for thepurpose under the action of the compressed gas in the first chamber 3.

The piston 2 has a projection 9 by which it enters the second chamber 4and delivers an impact upon the liquid.

To bring the piston 2 back to its initial position after an impact hasbeen delivered, supplied into the space of the cylinder 1 between thechamber 4 and the piston 2 is pressurized liquid fed by a pump 10 via amain 11 and through apertures 12 made in the sidewall of the cylinder 1,which apertures are overlapped by aspring-biased movable member 13 of alocking mechanism 14 after the piston 2 has delivered an impact upon theliquid contained in the chamber 4 and opened by said member 13 at theend of the piston 2 reverse stroke after an impact.

The space of the cylinder 1, disposed before the piston 2, is constantlycommunicated with the main 1! via a gap 15 between the body of thelocking mechanism 14 and the cylinder 1; periodical dis'communicationthereof is inex- 4 air-1A pedient as the time required for accelerationof the piston 2 and for delivering an impact upon the liquid isinsignificant as compared to the time of the working cycle.

Springs 16 displace the member 13 for overlapping the apertures 12 only.

During the piston reverse stroke the liquid from the space of thecylinder 1 enters the chamber 4, in which case the aperture 8 in thelatter is overlapped either by a turnable flap 17 (FIG. 1) connected bya rod 18 with the movable member 13 of the mechanism 14, or by a flap 19(FIG. 2) which is alternately actuated by a hydraulic 20 and a pneumatic21 cylinders connected with the main I1 supplying the liquid and withthe tank 6 containing compressed gas, respectively.

As has been stated above, the improvement in the devices describedherein relates to the locking mechanism 14.

In accordance with FIG. 3, the movable member 13 of the lockingmechanism 14 is provided with flange 22 disposed in a cylindrical recess23 of the mechanism body 24 and forming together with the latter anannular gap 25.

Provided in the body 24 is a space 26 open at the side of the flange 22and periodically communicated with the space of the cylinder 1 via theaperture 12. Besides, the body 24 of the locking mechanism 14 isprovided with an auxiliary space 27 periodically communicating with thepressure main 11, the butt end portion 28 of the movable member 13entering said auxiliary space 27 which is in constant communication viaan annular clearance 29 with the space 26 and, hence, with theatmosphere.

When made as described above, the locking mechanism 14 operates in thefollowing manner.

When supplied from the main 11 into the space 27, with the piston 2disposed after an impact in its extreme rear position in the chamber 3the liquid acts upon the butt end portion 28 of the member 13 andprovides for the beginning of motion of the member 13, whereupon thepiston 2 starts displacing in the cylinder 1 under the action ofcompressed gas in the chamber 3, thus forcing out the liquid disposedbefore it in the cylinder space.

With the liquid forced outby the piston 2 acting upon the butt endportion 28 of the movable member 13, the latter gradually displaces,overcoming the force of the springs 16. As soon as the butt end portion28 of the member 13, enters'the space 26 which, as a result, iscommunicated with the drain apertures 12, the liquid additionally actsupon the flange 22 making the member 13 displace-quickly and opencompletely the apertures 12. With the flange 22 having left completelythe cylindrical recess 23, there takes place gravity drainage of theliquid forced out of the cylinder space by the piston 2, and the piston2 is accelerated freely by the compressed gas.

The member 13 is held by the flow of the liquid being drained in itsextreme right position and compresses the springs 16. Then, after thepiston has delivered an impact upon the liquid in the chamber 4, theflow of the liquid being drained is sharply decreased and the member 13overlaps the apertures 12 under the action of the springs 16. Topreclude hydraulic impacts and vibration of the movable member 13 whileit is being moved to close the apertures 12, the cylindrical recess 23made in the body 24 turns into a cone-shaped recess 30, and, therefore,with the member 13 moving, the gap gradually decreases due to a decreaseof the flow of the liquid drained out of the space of the cylinder, theliquid forced from the space 26 being drained via the gap 25. The buttend portion 28 of the member 13 is tightly pressed against the body 24due to the liquid acting upon an inner annular recess 31 of the member13, whose diameter is greater than that of a packing flange 32 providedon the butt end portion 28.

The auxiliary space 27 is periodically communicated with the pressuremain 11 by means of a valve 33 (FIG. 1), which is actuated at the end ofthe piston 2 reverse stroke when the latter thrusts against the facewall of the cylinder 1 at the side of the chamber 3.

As soon as the piston 2 thrusts against the wall, the pressure of theliquid in the main 11 immediately rises,'since it is supplied into aclosed volume (the space of the cylinder 1 before the piston 2). As aresult of this, the plunger 34 of the valve 33 communicates the main 11with the space 27.

The pressure level for actuating the valve 33 should be higher than thatof possible accidental pressure jumps in the main 11 during the workingcycle.

The auxiliary space 27 may be dispensed with. For instance, the lockingmechanism 14 may be fashioned in such a manner that the butt end portion28 of its movable member 13 be in the main space 26 at the moment theapertures 12 are overlapped by this member.

The initial motion of the movable member 13 may be provided by othermeans as well. As shown in FIG. 2, the movable member 13 is connectedfor this purpose by rods 35 with a cross member 36 which abuts the facewall of the cylinder 1 at the side of the chamber 3 and has projection37 entering said chamber. At the end of the piston 2 reverse stroke,after it has delivered an impact upon the liquid, the piston 2 acts uponthe projection 37, thus making the cross member 36 displace togetherwith the movable member 13 connected therewith. Then, the lockingmechanism 14 operates in the aforedescribed manner and does not requirethe valve 33 as the initial motion of the member 13 is provided for bythe piston 2 proper.

The rod 35 should be made from two split portions 38 and 39, the portion38 having guide 40 provided at the end thereof and made as a frame inwhich a slide 4l secured to the end of the portion 39 moves. This designmakes it possible for the movable member 13 to move freely after thebeginning of its motion irrespective of the stroke of the cross member35.

The device made in accordance with the present invention provides for amore stable and efficient operation and does not require high skill onthe part of the personnel.

What we claim is:

A device for building up high-pressure impulse jets of liquid,comprising a tank containing compressed gas; a cylinder defining aninterior space; a piston disposed in said cylinder and dividing saidspace into two chambers, of which the first chamber is in communicationwith said tank containing compressed gas and the second chamber isfilled with liquid and has an aperture for the outlet of pressurizedliquid after an impact has been delivered thereupon by said piston inresponse to acceleration thereof by compressed gas in the first chamber;a pressure main supplying pressurized liquid into the space of saidcylinder to convey the piston so as to decrease the volume of the firstchamber after an impact; said cylinder having apertures in a sidewallthereof for draining liquid from the cylinder space during pistondisplacement in the direction of the second chamber; a locking mechanismwith a movable member for overlapping said drain apertures, saidmechanism being actuated at the end of the piston reverse stroke afteran impact; means adapted for the initial opening of said drain aperturesthrough the movable member when said piston is in the extreme rearposition in said first chamber; means providing for the full opening ofsaid drain apertures through the movable member in response to the flowof liquid forced out of the cylinder space during piston travel towardssaid second chamber; and means for moving said movable member so as toclose said drain apertures upon the piston delivering an impact upon theliquid.

2. A device as claimed in claim 1, wherein the means providing for thefull opening of the drain apertures by the movable member is essentiallya flange provided on said member and arranged with a gap in acylindrical recess in the locking mechanism body, and a main spaceprovided in said body, said space being opened at the side of saidflange and periodically discommunicated from the drain apertures in thesidewall of the cylinder by said movable member.

3. A device as claimed in claims 2, wherein the means adapted for theinitial opening of the drain apertures by the movable member is formedby an auxiliary space in the body movable member is formed by a crossmember connected by rods to said movable member, abutting the rearportion of the cylinder and having a projection entering the firstchamber of the cylinder and cooperating with the piston at the end ofits reverse stroke after an impact.

1. A device for building up high-pressure impulse jets of liquid,comprising a tank containing compressed gas; a cylinder defining aninterior space; a piston disposed in said cylinder and dividing saidspace into two chambers, of which the first chamber is in communicationwith said tank containing compressed gas and the second chamber isfilled with liquid and has an aperture for the outlet of pressurizedliquid after an impact has been delivered thereupon by said piston inresponse to acceleration thereof by compressed gas in the first chamber;a pressure main supplying pressurized liquid into the space of saidcylinder to convey the piston so as to decrease the vOlume of the firstchamber after an impact; said cylinder having apertures in a sidewallthereof for draining liquid from the cylinder space during pistondisplacement in the direction of the second chamber; a locking mechanismwith a movable member for overlapping said drain apertures, saidmechanism being actuated at the end of the piston reverse stroke afteran impact; means adapted for the initial opening of said drain aperturesthrough the movable member when said piston is in the extreme rearposition in said first chamber; means providing for the full opening ofsaid drain apertures through the movable member in response to the flowof liquid forced out of the cylinder space during piston travel towardssaid second chamber; and means for moving said movable member so as toclose said drain apertures upon the piston delivering an impact upon theliquid.
 2. A device as claimed in claim 1, wherein the means providingfor the full opening of the drain apertures by the movable member isessentially a flange provided on said member and arranged with a gap ina cylindrical recess in the locking mechanism body, and a main spaceprovided in said body, said space being opened at the side of saidflange and periodically discommunicated from the drain apertures in thesidewall of the cylinder by said movable member.
 3. A device as claimedin claims 2, wherein the means adapted for the initial opening of thedrain apertures by the movable member is formed by an auxiliary space inthe body of the locking mechanism, communicated with the pressure mainand adapted to receive the butt end portion of said movable member, saidauxiliary space being in constant communication with said main space inthe body of the locking mechanism.
 4. A device as claimed in claim 1,wherein the means adapted for the initial opening of the drain aperturesby the movable member is formed by a cross member connected by rods tosaid movable member, abutting the rear portion of the cylinder andhaving a projection entering the first chamber of the cylinder andcooperating with the piston at the end of its reverse stroke after animpact.